Although it may be used in principle for any multimedia message service and telecommunications network, an exemplary embodiment according to the present invention and the problem on which it is based are explained with regard to the MMS service (MMS=Multimedia Messaging Service), which is specified within the framework of the standardization of 3GPP (3rd Generation Project Program) and may be used, for example, in the GSM system (GSM=Global System for Mobile Communications) and the UMTS system (UMTS=Universal Mobile Telecommunication System).
There exists short message services, which may be used to send a short message to a subscriber of the telecommunications network without first having to establish a telecommunications connection to the subscriber.
This may be important in mobile radio communication systems such as GSM, since their subscribers may not be reached. In this context, incoming short messages for the subscriber may be stored by a telecommunications carrier of the telecommunications network, when the subscriber cannot be reached. At a later time, when the subscriber may be reached again, the short message is then automatically transmitted to the subscriber.
The SMS service (SMS=Short Message Service) is a short message service following the GSM standard. In this context, up to 160 7-bit ASCII message characters (ASCII=American Standard Code for Information Interchange) may be transmitted in a short message. Concatenated short messages permit the transmission of longer texts. Since only text transmission according to the GSM standard is provided, binary data, such as audio data, image data, etc., should be converted to text format when transmitted, and reconverted to binary format after being received.
In this process, it may only be possible to access the entire content of a short message. In this manner, data of the short message, which the addressed subscriber may not desire, may be transmitted to the subscriber, who only receives an overview of the content of the short message after having received the complete short message from the telecommunications carrier.
FIG. 4 shows the principal structure of a first type A of an SMS short message in GSM.
In general, an SMS short message SM of the first type A includes a header SM-H and a data portion SM-D. Header SM-H includes signaling inputs and the receiver address of a message to be sent, and the sender address of a message to be received. Data portion SM-D includes the actual message to be transmitted.
Transmitters and receivers are identified by the MSISDN (Mobile Subscriber Integrated Services Digital Network) number in accordance with GSM 03.40 V7.1.0 (11/1998) Technical Realization of the Short Message Service (SMS); Point-to-Point (PP) and 3G 23.040 V3.2.0 (10/1999) Technical Realization of the Short Message Service (SMS); and Point-to-Point (PP).
A second header (user data header SM-DH) may optionally be present in data portion SM-D. If so, then the presence of the second header is indicated by a corresponding signaling input in header SM-H. Various types of SMS user data headers are already specified in GSM 03.40/3G 23.040. Different types of user data headers SM-DH are distinguished by an identification element in user data header SM-DH.
The concatenation of short messages SM may be controlled, for example, by a user data header SM-DH (identifier: “08” hexadecimal). A further example of a user data header SM-DH is the “Wireless Control Message Protocol”, which is indicated by the identifier “09” in hexadecimal notation. This may be required for the Wireless Application Protocol (WAP).
FIG. 5 shows the principal structure of a second type B of an SMS short message in GSM.
In this case, an SMS short message SM′ may include a header SM-H′ and a data portion SM-D′. Header SM-H′ includes signaling inputs and the receiver address of a message to be sent, and the sender address of a message to be received. Data portion SM-D′ includes the actual message to be transmitted.
Header SM-H′ includes a field, which is 8 bits wide and referred to as the TP-PID (Transfer Protocol—Protocol Identifier). Parameter TP-PID may be used to establish the applied protocol. For example, it may be used to realize telematic interworking or to determine how messages are handled in the cellular phone or SMSC (short message service center).
In telematic interworking, the TP-PID is a bit pattern of the form <00xxxxx>, that is, bit 7=0, bit 6=0, and bit 5=1.
If this bit pattern appears in the TP-PID of header SM-H′ of an SMS short message SM′ sent by a cellular phone, then the SMSC (Short Message Service Center) is induced to convert the present SMS to a different data format and/or to execute a certain communications protocol. In this manner, e.g., a fax of the group 3 may be sent by a cellular phone to a fax machine in the fixed network. In this case, the value of the entire TP-PID octet is <00100010>.
If this bit pattern appears in the TP-PID of header SM-H′ of an SMS short message SM′ received by a cellular phone, then the SMSC has received a message from a non-SMS telematic service and converted it to an SMS. In this manner, e.g., an Internet e-mail may be sent from any e-mail account in the fixed network, via the service center, to a cellular phone. In this case, the value of the received TP-PID octet is <00110010>.
In the case of handling messages, the TP-PID is a bit pattern of the form <01xxxxxx>, that is, bit 7=0, and bit 6=1.
If this bit pattern appears in the TP-PID of the header SM-H′ of an SMS short message SM′ received by a cellular phone, then the SMSC causes the cellular phone to handle the message in a certain manner. In this manner, e.g., a cellular phone may be induced by the SMSC to relay the received message to the SIM (subscriber identity module), where it is then processed further in accordance with SIM application toolkits. In this case, the value of the received TP-PID octet is <01111111>.
If this bit pattern appears in the TP-PID of the header SM-H′ of an SMS short message SM′ sent by a cellular phone, then, e.g., in the case of the bit pattern <01000001>, the SMSC is caused to overwrite an already present short message of the same cellular phone with the received short message.
The MMS service is intended to permit the transmission and reception of multimedia messages, using a cellular phone. The current (temporary) state of standardization of MMS is found in 3G TS 23.140, MMS Stage 2, v.1.0.0. In contrast to an SMS short message, a multimedia message (MM) should not be limited to a certain length or to the display of only text. An MM should instead support various types of media.
The MMS relay has a central function in the MMS service. As shown in 3G TS 23.140, MMS Stage 2, v.1.0.0, this element may be connected to various servers (e.g. an email server, fax server, voice mailbox, and MMS server), using a large variety of media. Its purpose is to grant the mobile user access to all of the information/messages on the above-mentioned servers.
Thus, the MMS relay allows the mobile user access to e-mails on the e-mail server, or to faxes stored on a fax server, or to voice messages recorded in a voice mailbox, etc. Aside from the receipt of messages, the mobile user may write messages and send them to the desired recipient via the MMS relay.
3G TS 23.140, MMS Stage 2, v.1.0.0, provides for, inter alia, the user of the MMS service logging on to his MMS service provider (session establishment). The user may then obtain a receipt for the log-on (receipt), depending on a service profile. If the MMS server contains unread messages for the user, then the user may receive a message (notification) in accordance with his/her service profile.
In this regard, an MMS server may stand for one or more arbitrary servers, e.g., one or more e-mail servers, fax servers, special MMS servers (if an independent MM format is standardized), or an arbitrary combinations of these servers.
In the same way, the user may receive a message in accordance with his/her service profile, when a new message arrives at the MMS server during an MMS session.
If his/her profile is set up so that the user does not automatically receive notification of unread and/or new MM messages, then, according to the specification, the MMS service should allow the user to explicitly request such a notification from the MMS relay (explicit notification query).
In the service profile, the user may also specify whether he/she would like to receive a confirmation of the success of transmitting the MM's to other users from the service provider. In this connection, one may distinguish between two types.
The user may receive a reply from the MMS relay indicating that his/her sent message was successfully sent to the relay via the air interface:
(ACK/NACK submission 1: positive/negative acknowledgment of submission to relay).
In addition, the user may receive a reply from the receiver and/or from the MMS relay indicating that the receiver successfully received the message:
ACK/NACK submission 2=positive/negative end-to-end acknowledgment of submission to receiver.
The MMS service should also optionally permit the service provider (the MMS relay) to receive a reply regarding the success/failure of the delivery of an MM to a subscriber:
ACK/NACK delivery.
3G TS 23.140, MMS Stage 2, v.1.0.0, 3GPP TSG T WG 2, November 1999, also provides for the triggering of automatic downloading of messages by an SMS (pull-push).
The above-described functionality and messages regarding the MM are written in the applications level, but their implementation is open. This functionality and the messages, as well as similar functionality and messages, may be implemented in many different forms.
It is believed that a general problem is that, in the MMS message service, different types of messages are sent, such as the above-mentioned notifications from the system and actual user messages, whereby the latter may be varied in content, for example, short text messages or long video, audio, or other messages. As a result, it is believed that there is no transmission scheme that is equally optimized for all messages.